Sinestro was born on the planet Korugar in space sector 1417. His dedication to preserving order originally manifested in his previous career, an anthropologist specializing in reconstructions of ruins of long-dead civilizations. One day while he was on one such site, a Green Lantern named Prohl Gosgotha crash-landed into the site, injured and apparently dying. He quickly gave his ring to Sinestro, just in time for Sinestro, who barely even understood what the ring could do, to defend himself from the Lantern's pursuer: a Weaponer of Qward; however, Sinestro had to destroy the ruins he had spent time restoring in order to crush the Qwardian. Afterwards, Gosgotha turned out to still be alive and asked for his ring back to keep him alive long enough to get help. Sinestro, knowing this would mean not being a Green Lantern himself, instead let him die and took over his post. The Guardians were unaware of his actions.[2]

In Green Lantern #45, his wife is shown for the first time in a flashback and revealed to be the sister of Abin Sur.

When Hal Jordan joined the Green Lantern Corps, Sinestro was assigned to be his instructor. Jordan was horrified at his new mentor's totalitarian methods, though Sinestro maintained that his iron-fisted rule was necessary to protect his people from alien forces. During his training, Jordan helped Sinestro repel an attempted invasion of Korugar by the alien warlords known as the Khunds. When Jordan called for help from the other Green Lanterns, Sinestro's dictatorship was exposed and he was forced to appear before the Guardians for punishment. Katma Tui, the leader of a Korugarian resistance movement who felt that Sinestro's "protection" kept her people from growing as a society through contact with other alien races, was recruited as his replacement in the Corps. Though Katma Tui eventually grew into one of the most respected Green Lanterns, she and the rest of Korugar initially resisted her appointment to the Corps; due to Sinestro's actions, Korugar had come to consider the symbol of the Green Lantern Corps an emblem of terror and oppression.

For using the power of the Green Lantern to instill fear rather than combat it, the Guardians banished Sinestro to the antimatter universe, a counterpart to the "real" universe made up of "negative matter". Sinestro ended up on the antimatter world of Qward, that universe's counterpart of the Guardians' homeworld Oa, which was ruled by a race of warriors and scientists known as the Weaponers of Qward, who bore a fierce hatred of the Guardians and all Green Lanterns. By exiling Sinestro to a world ruled by evil beings who specifically hated him as a Green Lantern, the Guardians hoped to humble him. However, their attempt at punishment would be a major miscalculation. Sinestro believed himself to have been wronged by his former masters and now hated them just as much as the Weaponers did. Through their mutual hatred of the Guardians, Sinestro and the Weaponers became allies, with the Weaponers offering to help Sinestro gain revenge on the Guardians and the Corps.

Creating a yellow power ring for Sinestro to use, the Weaponers sent him back to the "positive matter" universe to seek his revenge. Sinestro quickly became the Green Lantern Corps' most powerful nemesis, partially due to a weakness in their power rings that prevented them from directly affecting the color yellow. Despite this, skilled Green Lanterns like Jordan, Sinestro's most hated enemy, always found ways to defeat him.

Pre-Crisis Sinestro first met Hal when he had already made an alliance with Qward. Hal had already beaten the Weaponers three times. Sinestro tried to kidnap him using a device which could transport people to Qward and was able to imprison him in a yellow bubble by threatening to kill 100,000 people who had been kidnapped with the device when he used it on a city Hal was supposed to be at. However Hal used his ring to speed up a clock, making Sinestro think his ring had run out of power. When he released Hal from the bubble to eliminate him, he was defeated and imprisoned in a green bubble by Hal, who did not take him back to his universe as it would go against the jurisdiction of the Guardians. However he escaped using a ring that could drain the Green Lantern's ring-power and continued to menace Hal. He tried to attack the Guardians after trapping Jordan, before disguising himself as Hal so he could occupy a meeting of Green Lanterns and absorb power from their rings by casting an illusion of a monster so that they would use their rings. However, Jordan escaped and defeated Sinestro on Oa, who was placed in a green energy container which would orbit the Universe by the power of many Green Lanterns, but he escaped with a power ring hidden in his boot. He was very adept at escaping the ways the Guardians tried to imprison him.

Before the Guardians took a leave of absence from their universe to attempt mating with their female counterparts, the Zamarons, they constructed an inescapable prison for Sinestro and thousands of others on Oa. Sinestro managed to free himself through the mental manipulation of the Mad God of Sector 3600. Wielding nearly unlimited power, Sinestro murdered entire star systems until he was finally subdued by the Green Lantern Corps of Earth. Guilty of multiple acts of genocide, Sinestro was put on trial again by the assembled membership of the Green Lantern Corps. Finding him guilty, they condemned him to death and executed him, but Sinestro managed to cheat death itself by sending his essence into the Central Power Battery and shutting it down. While in the Battery, he also made a startling discovery about the ancient weakness to yellow within the Green Lanterns' light.

Hal Jordan entered the Battery in a desperate attempt to restore the powers of his fellow Lanterns and ultimately defeated Sinestro, whose spirit was condemned to remain trapped inside the Central Battery, powerless, for eternity. Yet Sinestro had earned an even greater personal victory as the so-called "yellow impurity" turned out to be a sentient entity known as Parallax, the living embodiment of fear. He also discovered the battery's power source was Parallax's green counterpart, Ion, the embodiment of willpower.[3] Thanks to Sinestro's actions, Parallax successfully infected Jordan's mind, leaving the so-called "greatest Green Lantern" vulnerable to fear for the first time in his life and setting up Sinestro's ultimate triumph.

Sinestro's original yellow ring was stolen by Guy Gardner from Oa's Crypt of the Green Lantern Corps. During the encounter, Sinestro possessed John Stewart to confront Guy, but his spirit was not strong enough to defeat Gardner's willpower.

As the yellow ring only "spoke" Sinestro's native language, Guy was unable to communicate with it, although it seemed to understand him to a degree.

Guy only wore the yellow ring for a short time before Hal Jordan, possessed by Parallax, destroyed it.

In the meantime, the return of the Guardians resulted in the Corps being re-established. However, the newly restored Corps would be short-lived, thanks to the inadvertent efforts of the alien warlord Mongul and Hank Henshaw, a cyborg who was at the time impersonating Superman. As part of their ultimately thwarted plot to transform Earth into a new version of Mongul's interstellar fortress Warworld and gain revenge on Superman, Mongul and the Cyborg used several nuclear devices to completely destroy Coast City, California, which was Hal Jordan's home, and everyone living in it. Driven mad with grief by the destruction of his city and the Guardians' apathy towards his plight, Jordan's previously indomitable willpower was shattered. Parallax was thus able to possess him completely and push him towards a homicidal rampage that wiped out most of the Guardians and left scores of Green Lanterns dead or maimed, as Parallax sought to absorb the Central Power Battery's energies into his being.[volume & issue needed]

As a last-ditch effort to halt Jordan's rampage, the Guardians freed Sinestro from the Central Power Battery and sent him to stop Jordan. Though Jordan snapped Sinestro's neck after the battle, apparently killing him, it would later be revealed that what the Guardians had actually extracted from the Battery was a hard-light construct of Sinestro, created by Parallax and mentally puppeteered by the real Sinestro from within the Battery. Parallax then bonded to Jordan, who took the entity's name for himself, and promptly finished off the Green Lantern Corps by absorbing the Central Battery's energies into himself. With the Battery destroyed, Sinestro escaped and went into hiding as he watched Jordan become what he had always hated Sinestro for being: a traitor and a murderer reviled by his friends and his allies. When the last surviving Guardian, Ganthet, gave the last remaining power ring to Kyle Rayner, Sinestro became obsessed with the young Earthman, realizing that despite Jordan's downfall, his plot to extinguish the Green Lanterns' light had failed.[volume & issue needed]

During the period when he was believed to be dead, Sinestro had two indirect encounters with other heroes. When dealing with an artificial intelligence based on the dead son of its creator, Wonder Woman faced a duplicate of Sinestro created by the A.I.'s use of a life-replicating material while watching videos of Sinestro's old battles, believing that he was just playing a computer game and unaware of the real-world damage that he was causing. Although he lacked Sinestro's tactical genius, his unrestrained use of Sinestro's power destroyed a bridge and a building, nearly suffocating Wonder Woman before he was defeated by the hero Champion (really a disguised Hercules).[4]

On another occasion, Kyle Rayner was accidentally sent approximately a decade into the past, where he found himself witnessing a battle between Hal and Sinestro. Although he initially distracted Hal at a crucial moment, Kyle's ring's immunity to yellow proved vital in preventing Sinestro from executing the Guardians of the Universe. Kyle and Hal subsequently sabotaged his attempt to crash a planetoid into Oa by switching rings, Hal allowing Sinestro to throw him away before using Kyle's ring to destroy Sinestro's equipment while Kyle kept Sinestro occupied, using Hal's ring to protect him from mortal injury. However, after Sinestro's actions resulted in Hal unintentionally traveling to Kyle's future,[5] this encounter was apparently erased from history when Hal, Kyle, and a Parallax-possessed older Hal Jordan (who had detected his younger self's displacement and intervened to try and send him home) worked together to send Hal and Parallax back to their proper place in time to ensure that a Hal Jordan was present with powers to defeat the Sun-Eater, Hal returning to his own time just before Kyle's arrival changed history and defeating Sinestro on his own.[6]

Later, Hal Jordan's Spectre also clashed with the ghost of Sinestro,[7] who traps him in a dream where he never became a Green Lantern. Upon his defeat, Sinestro is given the chance to choose his fate. He chooses Hell, and is dragged into the Underworld by a fiery hand. In retrospect, it is assumed that this version of Sinestro is another hard light construct created by Parallax at Sinestro's behest, as the fear entity is still bonded to Jordan's soul during his time as the Spectre, continuously breaking his will.

Sinestro eventually revealed the charade of his 'death' when Kyle Rayner discovered the existence of Parallax and revealed it to Green Arrow and the Justice League. Nearly killing the two heroes, Sinestro was stopped by the newly resurrected Hal Jordan, who reclaimed his ring and was purged of Parallax's influence. The two fought to a draw, with Sinestro escaping to the antimatter universe when his ring was damaged by Hal during the fight.[8]

Sinestro later appeared in the mini-series Villains United, in which he captures Lady Quark for the Secret Society of Super Villains, a group of which Sinestro had previously been a member. Here he plays a major role in the Society's massacre of the Freedom Fighters, who are investigating the meeting place of other villains, but walk into an ambush. Sinestro begins the fight by blowing a hole through the chest of the second Black Condor, killing him instantly. He then defeats Uncle Sam, leaving him for dead.

After the Battle of Metropolis, Sinestro retreated to the antimatter universe. He made a pact with the Anti-Monitor and embraced the doctrine of spreading fear. The Green Lantern Corps is once again reformed with the return of Hal Jordan so Sinestro decides to found the Sinestro Corps, offering yellow power rings and a role in the Corps to the most feared and savage warriors of the universe. He is also revealed to have masterminded the death of Kyle Rayner's mother by having the sentient virus Despotellis invade her as part of a plot to break Kyle's will so that he can become Parallax's latest host.

The Sinestro Corps War begins with an attack on Oa. Sinestro himself returns to Korugar to confront his successor, Soranik Natu. Sinestro defeats her, but makes it appear she has defeated him. This will force her to stay on Korugar to fulfill her responsibilities as "the Savior of Korugar".[9]

Sinestro returns to Qward and joins the battle occurring there. He confronts Earth's Green Lanterns, and upon their escape, follows them toward Earth, the Sinestro Corps' real target.[10] The Sinestro Corps begin attacking Earth. Sinestro reveals to Hal, Guy and John that he intends to turn Earth into the new homeworld for the Sinestro Corps and the site of the new Coast City into a mass graveyard, "A mecca of fear".[11] During the battle, the Guardians enacted new laws to the Book of Oa. The first new law was to give the Green Lanterns the ability to use lethal force. Sinestro claims he has achieved his overall goal because now the Green Lanterns spread fear by being unchecked. Hal Jordan and Kyle Rayner beat Sinestro in hand-to-hand combat.[12] Sinestro is then imprisoned in Oa's Sciencells where he learns from Hal Jordan that he has received a death penalty. Despite his personal defeat, Sinestro claims victory. Sinestro's overall goal through his war was to groom his former Corps for a more active, forceful role in the universe. With the enactment of the Corps' new laws and the approval of lethal force, the Green Lantern corps will inspire fear, creating the same effect as the Sinestro Corps: order through fear.

With the hunt for the members of the Sinestro Corps becoming one of the Green Lantern Corps' highest priorities, many of those who wield yellow power rings have been incarcerated in Oa's Sciencells, with their power rings stored in the large chamber that houses the entire detention facility. Sinestro has been shown to have chewed a very large hole in his finger, and he used his blood to paint the insignia of the Sinestro Corps on his cell window. All Sinestro Corps members followed his example, with the result of thousands of emblems across the cosmic jail. When Sinestro formed his insignia from blood, the power rings stationed on Oa seemed to react violently, threatening to break free of their confines.

Sinestro is to be executed on his homeworld of Korugar. During the transport, a group of Sinestro Corps members attempt to free him. Atrocitus and his Red Lanterns intervene by attacking both Corps and kidnapping Sinestro. In the midst of the battle, a Blue Lantern named Saint Walker tells Hal Jordan that Sinestro's survival is crucial in order to stop the Blackest Night.[13] After being taken to Ysmault, he is nailed to a cross to await his execution at the hands of Atrocitus, who wishes to make Sinestro suffer greatly by taking his revenge on everything he has ever cared about. His targets include Korugar and Sinestro's hidden daughter.[14] Sinestro breaks free and goes back to his home world to see to family business.[15][16]

After escaping the assault by the Red Lanterns, Sinestro finally reaches his homeworld of Korugar. After rapidly incapacitating Princess Iolande, he confronts Soranik Natu and reveals that his wife took Soranik and left him as he began his rise to power on Korugar. He was eventually able to locate his daughter and give her the mark on her face, his family's coat of arms, along with a micro-transmitter so he could locate her. He visited Soranik throughout her life using his ring to alter his appearance. He even took a picture of her and the Natus at her medical school graduation. Sinestro then says that he is proud of his daughter for succeeding where he could not, namely bringing order to Korugar as a member of the Green Lantern Corps. He then tells her that they must work together to stop the Blackest Night.[17] After leaving Korugar, Sinestro travels to visit the grave of Abin Sur and makes plans to lead an assault on the homeworld of the Star Sapphires.[18]

When he arrives, he first encounters Carol Ferris. While Sinestro holds no ill will towards Carol and only wishes to free his Corpswomen from Zamaron, he warns Carol that he will hurt her if she stands in his way. Carol then encases Sinestro in a crystal structure, forcing him to relive the death of his love, Arin Sur (Abin Sur's sister). Angered by this, Sinestro bursts free, staggering Carol enough for his Corpsmen to seize her. However, before he can capitalize on the advantage, the Black Lanterns invade, led by Amon Sur, shocking both Sinestro and Carol.[19] Hal Jordan and Indigo-1 then appear, initially fighting off some of the Black Lanterns. Indigo-1 teleports the group to Korugar so that Sinestro may finally confront Mongul. Sinestro defeats Mongul by overriding his rings, then imprisons him within the Yellow Central Battery. Sinestro vows to keep Mongul alive (and torture him), then kill him when the Blackest Night is over. He also proclaims himself to be "leading this coalition" against the Black Lanterns. The Sinestro Corps' celebration is cut short when a ship crash lands nearby, containing Black Lanterns Abin and Arin Sur.[20]

As the Black Lanterns attack, Sinestro is emotionally manipulated by the corpse of Arin. At one point, the corpse even alters itself to look more like a living person and addresses Sinestro by his full name (revealing his first name, Thaal, for the very first time). Just then Hal, Abin and Carol burst through the streets to where the others are. With all four in place, they destroy Abin's and Arin's rings. Afterward, Hal and Sinestro debate whether to contact the Blue or Red Lanterns, respectively. Hal then makes the decision himself. Sinestro relents, tells his Corps that there is a temporary truce with the GLC, and travels with the others to Odym.[21] After gathering the other Corps leaders, Sinestro and the others follow the Black Lantern battery to Earth, where Nekron has already risen. Under Indigo-1's direction, they combine their lights, thinking it will destroy the Black Lanterns' source of power, but this fails[22] and in an attempt to bolster their ranks, Ganthet duplicates the Corps leaders' rings, having them seek out candidates to deputize. Sinestro's ring chooses the Scarecrow.[23] The Black Lantern Spectre then attacks the group. In order to defeat it, Hal releases Parallax from its prison, intending to let it possess him again. Sinestro offers to join with Parallax instead, but is rebuffed.[24] When the restored Spectre manages to separate Parallax from Hal, Sinestro again tries to claim the fear entity as his own, but is foiled when Parallax is pulled away by an unknown force.[25]

In the midst of the battle, Nekron kills a Guardian and uses its blood to summon a large white figure from Earth. Ganthet reveals this is the Entity, the living embodiment of the life force of the universe. It seems Earth is where life first began, a fact the Guardians did their best to hide so as to keep the Entity safe. Outraged at how the Guardians' need for control caused the death of Abin Sur, Sinestro stabs Ganthet with his ring. Hal Jordan realizes the Entity needs a mind to guide it and prepares to fly in, but Sinestro cuts him off. He dives into the white energy and emerges as a figure all in white, declaring he is about to show the universe he truly is the "greatest Lantern of them all". Entity intones "Thaal Sinestro of Korugar...Destiny awaits".[26]

During the confrontation with Nekron, Sinestro is apparently killed by Nekron, but healed back to life by the White Entity, claiming to be in harmony with every living being in the universe and thus reborn as the true Guardian of the Universe.[27] However, Sinestro proves unable to fully control the Entity's power because of his ego-maniacal personality, and Nekron is able to separate them. Hal then comes to the realization that, even though Nekron allowed the various resurrections of the heroes he transformed into Black Lanterns, it was they who chose to live again. This enables Hal to access the Entity's power and transform himself and the other heroes into White Lanterns, resurrecting Black Hand and breaking Nekron's tether to the living universe. As the various corps part ways, Sinestro notes that Larfleeze himself has changed, as he actually returns Lex Luthor to the other gathered Corps rather than keeping Luthor for himself after he was forced to briefly share his power with the bald billionaire.[28]

In the Brightest Day crossover, Sinestro discovers a white power battery in a crater on Earth. In the first issue of the "New Guardians" story arc, Sinestro reveals that the white power battery wants Hal Jordan.[29] He and the other Corps leaders must pursue Krona, who is trying to capture all of the emotional entities. Sinestro must also work with Kyle Rayner and the Green Lantern Corps in an effort to rescue Soranik Natu from a Qwardian who made Sinestro's original yellow ring.[30]

In the War of the Green Lanterns storyline Sinestro and the other 'New Guardians' are trapped in the Book of the Black by Lyssa Drak while trying to recover the emotional entities from Krona. Hal Jordan alone is able to avoid the book and escapes with the other "New Guardians's" rings.[31] He later uses Sinestro's ring when Parallax is returned to the Central Power Battery, allowing Krona to control all Green Lanterns. Hal and others escaped only thanks to their prior experience with Parallax granting them an immunity to the initial assault, in order to give himself a weapon against the other Lanterns.[32] While attempting to escape the Book which forces the New Guardians to re-live their lives prior to acquiring their current rings, Sinestro discovers Indigo-1 in a prison cell, angrily proclaiming that she will escape whatever Abin Sur has planned for her, although he chooses to focus on his own escape rather than remain to question her more about this, only for Krona to burn the page that Sinestro is on before he can escape.[33] Sinestro and the others are later freed by Kyle Rayner, who 'draws' their escape. Sinestro's ring attempts to return to him, but is overridden by Krona, who wields all seven varieties of power rings. As Hal Jordan battles Krona, Sinestro hears him as he declares his dedication to the cause of the Green Lanterns and is inspired to join his old enemy in battle. As he fights Krona, a green power ring comes to him, making Sinestro a Green Lantern once more.[34] Sinestro is not interested in becoming a Green Lantern, but the Guardians of the Universe convince him to join the Corps.[35] Later, when the Green Lantern Corps are in disagreement and attempt to kill him, the Corps break into the sciencells, but they discover that Sinestro was in captivity by the Guardians, who are trying to remove Sinestro's green ring, but the ring will not be removed. Later, the Green Lantern Corps were in a meeting with the Guardians and told that they should choose between discipline, continuing the fight, and starting a mutiny. The other Green Lantern Corps are in agreement.[36]

In September 2011, The New 52 rebooted DC's continuity. In this new timeline, Sinestro is angry that he has a Green Lantern power ring. The Guardians of the Universe state that the ring wishes to redeem him.[37] With the aid of Hal Jordan, Sinestro returns to his home world of Korugar and liberates his people from the out-of-control Sinestro Corps.[38] Disabling his former group by rendering them comatose, he heads back out into space with the intent of shutting down the entire Sinestro Corps.[39]

Later, he witnesses the prophecy of the Guardians' plans for a "Third Army" and once again retrieves Hal from Earth. However, he is captured by the Indigo Tribe and is forcibly bound to an Indigo ring.[40] Hal convinces the Tribe that he can help Sinestro atone for his past deeds without being bound to an Indigo Ring.[41]

The two then retrieve the Book of the Black to glean information about the future, but it inadvertently takes them to the evil Black Hand. Elsewhere, the Guardians discuss how they willed Hal's ring to claim Sinestro in order to undermine all the other Corps, especially his own.[42] Black Hand engages Sinestro and Hal in combat, whereupon the Guardians arrive and command Black Hand to kill both Green Lanterns. As their life is drained away, Hal and Sinestro fuse their rings together and send off the resulting ring to get help.[43] Soon after, Hal and Sinestro are banished to the Dead Zone.[44]

They wander the Dead Zone searching for a way to escape[45] and encounter the deceased Tomar-Re. He asks Sinestro and Hal to stop Volthoom, the First Lantern.[46] When Simon Baz enters the Dead Zone during a fight with Black Hand, a way out is provided by Green Lantern B'dg. Sinestro reclaims the green ring and exits the Dead Zone with Simon.[47]

Sinestro then teleports to his home planet of Korugar to rally support against the First Lantern. Volthoom attacks and consumes the hopes and fears of the Korugarians. With his new found power levels, Volthoom destroys the entire planet, leaving Sinestro in the rubble.[48]

When Kyle Rayner and Carol Ferris arrive at Korugar's remains, Sinestro attacks, but immediately notices that Kyle is now a White Lantern. Sinestro demands that Kyle resurrects Korugar, but Kyle is unable to do so. Sinestro takes the white ring to become a White Lantern himself, but it rejects him as an unsuitable host. He then claims the yellow power battery instead and leaves to exact revenge.[49]

He arrives on the planet Oa and strikes Volthoom, but their battle is interrupted by the Indigo Tribe. The Tribe opens a portal to the Dead Zone, allowing Hal to escape as a Black Lantern. Volthoom engages Hal and reality begins to unravel.[50] Sinestro turns to the Yellow Central Power Battery and releases Parallax, becoming its new host in order to attack Volthoom with heightened power levels.[50] Volthoom is ultimately defeated when Hal Jordan summons Nekron.[50]

Afterwards, Sinestro reactivates his Sinestro Corps and heads off to kill the Guardians for all the harm that they have caused.[50] Hal attempts to talk Sinestro out of this course of action in order to save him from himself. However, it was too late as Sinestro reveals that he had already killed the Guardians before Hal intercepted him.[50] Sinestro vanishes and leaves Arkillo in charge of the Sinestro Corps. Reappearing elsewhere, Sinestro secretly brings Ganthet and Sayd together, stating that he knows what it is like to lose everything, but exiles them both from Oa.[50]

During the Forever Evil storyline after Batman uses a yellow ring, Sinestro appears to confront Power Ring.[51] Sinestro follows Power Ring through the sewers, eventually severing his right arm and allowing his ring to go search for a new host. Relieved to be free, Power Ring dies, thanking Sinestro.[52] After that, Sinestro joins Batman, Catwoman and the rest of Lex Luthor's team into taking down the Crime Syndicate.[53] When it comes to the final battle against the Crime Syndicate, Sinestro and Black Adam move the moon where the sun ends up weakening Ultraman. In the aftermath of the battle against the Crime Syndicate, it was stated that the villains who helped to stop the Crime Syndicate would have their criminal records wiped. Sinestro and Black Adam did not care about that; they begin laughing since they know the rules do not apply to them and went their separate ways, along with the other villains.[54]

Sinestro then travels to a monastery on a planet. In it, he finds runes that could help him 'purge' the entity from his system. After doing so, he simply meditates there, awaiting death. Then Lyssa Drak appears before him and tries to convince him to come back. He refuses, even when she says Arkillo is making a mockery of the Corps, creating thousands of rings for anyone who will swear loyalty to him. Then she reveals his people are still alive. When he asks how she knows this, she reveals she has carved every word from the Book of Parallax on her body. When Sinestro realizes that the remaining Korugarians are suffering because of his inaction, he feels fear again and his ring reactivates.[55]

After rescuing a group of pods containing some Korugarians from the servants of the Pale Vicars, Sinestro and Lyssa Drak head to the refuge of the Sinestro Corps where he is challenged by Arkillo who currently leads the Yellow Lanterns as the Arkillo Corps and has Soranik Natu as his captive. Arkillo and the Yellow Lanterns attack Sinestro who manages to defeat them and forces Arkillo to yield and kills a Yellow Lantern who tries to attack him from behind, melting his ring to stop it from finding a replacement. With his leadership retained, Sinestro sends Arkillo to the infirmary and Soranik argues with him, believing he had her captured. Refuting this, Sinestro shows her the Korugarians he saved and asks her to help them, but not before sending her to check up on Arkillo. Sinestro creates an elite team to personally serve him, consisting of Lyssa Drak, Rigen Kale, Dez Trivius, Romat-Ru and the most vocal Sinestro Corpsmen and has them aid himself in taking Necroplis as the new planet for the Korugarians and the moon for the Sinestro Corps.[56] Returning to his base of operations to prepare for the move to Necropolis, Sinestro and Soranik meet with the recently awakened Korugarians who voice their distrust of Sinestro despite his intentions. Sinestro brings a Green Lantern Power Battery for Soranik to recharge and she joins his team in rescuing a group of Korugarians that are being sold into slavery on the planet Muz.[57]

After rescuing them, they are attacked by the Paling. The Sinestro Corps defeats them and Sinestro executes them all. On their way back, Soranik reveals she left the rescued Korugarians with Hal Jordan,[58] which angers Sinestro, who then attacks him. Sinestro's elite team joins the fight but Sinestro calls them off say that he and Hal can have a 'civilized' discussion at a safe location for the Korugarians. Hal berates Sinestro for allowing Parallax to control him and kill the Guardians, which Sinestro refutes. He proves to Hal that he is in control and summons Parallax to attack Hal, then calls it back, proving that he has mastered fear itself. Leaving Hal behind, Sinestro leaves with his team and the Korugarians, with Soranik leaving with him to look after her people.[59]

In the aftermath of the war with the New Gods of New Genesis, Sinestro has created Warworld into the new base and headquarters of the Sinestro Corps, after the Green Lantern Corps were apparently dissolved.[60]

Subsequently, in DC Rebirth, Warworld transports to the ruins of the planet Oa, while Sinestro (with seemingly old age) plans to control the universe. When Sinestro senses the spectrum of green light, he enters the core with Parallax.[61] He possesses the fear entity of Parallax again and returns to his youth. He sends out his enforcers of his Corps to control the new order of the universe with fear.[62]

When Sinestro is stunned that his Corps have reports that Hal Jordan has returned and attacks the Corps, his daughter, Soranik Natu rebels against her father, saying that he should take responsibility for his failures and that he will never learn from the Green Lantern Corps.[63] Later, Sinestro alliances with the priests of the Sacrament, who are an enemy of the Green Lantern Corps, who reconsider him to aiding enforcement controls of the Vega system.[64] His Corps has captured Green Lantern Guy Gardner, instead of Hal. Sinestro is furious and demands to know where Hal is, but he learns that Soranik has secured Hal safely. Sinestro then uses the imprisoned people in Warworld's engine to increase the power of fear for his Corps, while he tries to interrogate Guy to where the Green Lantern Corps are.[65]

Later, Sinestro feels he is in jeopardy now that the Green Lantern Corps have returned, including the fact that his daughter, Soranik, has rejected his Corps.[66] He increases his Parallax powers to one thousand percent when Hal returns and invades Warworld. Sinestro orders his Corps to stop intervening in his personal fight against Hal and confronts his former pupil face to face.[67] During the battle, Sinestro discovers too late that his powers have decreased due to Soranik rescuing people that were used to power the Fear Engine. Hal then uses his energies as a living construct to incinerate the Fear Warlord and destroys Warworld, apparently sacrificing himself and killing Sinestro in the process.[68]

Later, it is revealed that Sinestro survived from the attack, is critically injured and that he and Lyssa Drak were teleported to Qward.[69]

The Green Lantern and Sinestro Corps under Soranik Natu form an alliance against the encroaching Dark Multiverse. Sinestro initially plans to cooperate but is met at the Source Wall by Lex Luthor, who invites Sinestro to Earth to join his Legion of Doom. Attracted by the promise of the "Invisible Emotional Spectrum", a source of power Sinestro became aware of in his youth just before joining the Green Lanterns, Sinestro abandons the Corps and travels to Earth. Reverting to his original Silver Age costume, and wielding the power of the Ultraviolet Corps rather than his Qwardian power ring, he successfully brainwashes half the planet and begins to bring the black sun Umbrax, source of the Invisible Spectrum, into the universe. After the plan is foiled, he remains an ally of Luthor.

Sinestro wields a yellow power ring that is functionally similar to those of the Green Lanterns, granting him flight, the ability to survive in any environment and the ability to create constructs of any shape and size. The ring must be regularly recharged with the aid of a power battery shaped like a lantern.

As a host whose body reined in and mastered the Emotional Embodiment of Fear, Thall Sinestro now acts as the host as well as containment vessel for the emotional entity of his Corps; Parallax gives him unprecedented power both physical and metaphysical in nature. Like previous hosts before him, Sinestro has vast reality-altering abilities enabling him to twist and bend time, space, matter and/or energy to his liking; likewise all of his natural power stemming from his ring are amplified to incredible degrees enabling the creation of stronger constructs and greater plasma discharge. Physically, the Master of Fear gains a dynamism boost as well, putting him on par with some of DC's strongest characters such as Superman or most notably Black Adam, shown when both he and Adam moved Earth's moon out of the path of its sun together,[54] or when he was under assault by equally powerful assailants such as Superwoman, Deathstorm and Alexander Luthor who had stolen multiple powers.[53]

The visual design of Sinestro was based upon British actor David Niven.[70][71] However, the alien features of Sinestro's physical appearance have been depicted inconsistently in both comics and animation over the decades.

Sinestro's skin color (and that of other Korugarians), although often diegetically described as simply "red", is rarely depicted as such, ranging from pink, deep scarlet, purple and, perhaps most commonly, magenta, depending on the colorist.

Additionally, many artists portray Sinestro with an upwardly elongated forehead (similar to the original design of Hulk villain the Leader, albeit less extreme), while others artists have bestowed him with more human cranial proportions. He was initially bald, but now boasts a human-like head of raven hair. The villain's ears are also inconsistently depicted, being frequently drawn with tapering pinnae in the same manner as Vulcans and Elves, yet he is also commonly shown to have human-shaped ears instead. Oddly, other characters from Korugar such as his successor Katma Tui and even his own daughter Soranik Natu are virtually never depicted with these features of either the tall forehead or elfin ears.

Additionally, due to the fact that his name is derived from the Latin word sinestra, meaning "sinister" or also "left" and "left handed", and commonly associated to wickedness, Sinestro has been often depicted in the comic books as left handed.[72] This trait has also been faithfully portrayed in other media, such as the animated film Green Lantern: First Flight and the live-action film Green Lantern.

In the final issue of DC Comics' 2006-07 year-long weekly series, 52 #52, it was revealed that a "Multiverse" system of 52 parallel universes, with each Earth being a different take on established DC Comics characters as featured in the mainstream continuity (designated as "New Earth") had come into existence. The Multiverse acts as a storytelling device that allows writers to introduce alternate versions of fictional characters, hypothesize "what if?" scenarios, re-visit popular Elseworlds stories and allow these characters to interact with the mainstream continuity.

The 2007-08 weekly series Countdown to Final Crisis (or simply Countdown) and its spin-offs would either directly show or insinuate the existence of alternate versions of Sinestro in the Multiverse. For example, Countdown #16 detailed that the Sinestro of Earth-51 has been murdered by the proactive Batman of his world in a crusade against its villains. Countdown spin-off series Countdown Presents: Lord Havokand the Extremists depicted a version of Sinestro in its third issue (2008) from an alternate world referred to as "Green Sinestro", depicted as a part of the villainous Monarch's army. This version has his original green power ring, but is no less vicious than his mainstream continuity counterpart and the official designation of his world is unrevealed.

In Superman & Batman: Generations - an AU where all heroes are shown aging in real-time, Sinestro attacks Earth to try and eliminate Hal Jordan - who here went into politics rather than heroism, rising to the position of President in the 1980s, but is defeated when Jordan dons Alan Scott's ring, having realised that the rings actually have no vulnerabilities except what the user believes they possess.

In the alternate timeline of the Flashpoint event, Sinestro is still a Green Lantern, and his mentor Abin Sur is still alive. The duo's friendship has become strained due to the death of Abin's sister Arin. After Abin is sent to Earth by the Guardians, Sinestro approaches the imprisoned Red Lantern Atrocitus on Ysmault, seeking information about the prophecy related with the "Flashpoint".[73] Having learned that the "Flashpoint" is a moment when all of history will be changed, Sinestro travels to Earth to confront Abin Sur, determined to find the "Flash" who changed history and use his power to reset the universe to what he believes it should be.[74] During the struggle, Abin Sur destroys his ring and imprisons him. Abin Sur then contacts the Guardians of the Universe to expel Sinestro from the Corps.[75]

In the distant future, a Green Lantern named Toris serves as the bookkeeper on Oa. A rookie Green Lantern named Snow wishes to hear the tales of the greatest Green Lanterns in history. Toris opens the book of Oa and proceeds to tell him the legend of Hal Jordan. After his storytelling is done, Lantern Snow asks about the other Green Lanterns of Earth and their lives after, and Toris elaborates even further on their eventual destiny. When Lantern Snow asks about the fate of Sinestro, Toris claims that they will never know what happened to him since he burned the book's pages of Sinestro long ago, saying it was for the best. It is heavily implied that Toris is none other than Sinestro himself.[50]

In the possible future of Futures End set five years, the Sinestro Corps are attacked on New Korugar by the Apex League. With the Corps being decimated by the league, Soranik (who has joined the Sinestro Corps) pleads with her father to release Parallax. Sinestro refuses as its release would destroy the planet. He decides to lead the league away, along with Lyssa Drak, in order to save the planet. This succeeds, but the Apex League captures Sinestro and imprisons him within the Tartaros Ultra-Max Penitentiary. Sinestro devises a way to escape and is aided by the former keeper of the Indigo Light, Natromo. Lyssa Drak appears before Sinestro, revealing she has found the weapon he desires. Natromo presents a trinket (created from parts Sinestro scavenged for him) to Sinestro, allowing him to use the light of fear again and stages a prison break with a group of inmates. Sinestro meets with the ghost of Lyssa Drak who fulfills her final obligation and disappears, leaving behind her skull which Sinestro takes. After landing on New Korugar, Sinestro kills the other inmates and observes the corpse filled, wasteland of his former planet. The Apex League confronts him, revealing that an angry and hungry Parallax freed itself from the planet's core, stripped the Sinestro Corps of their powers and devoured them. Sinestro blames the Apex League for this and smashes Lyssa Drak's skull on the ground. A Black Lantern Power Ring emerges from the skull's remains and transforms Sinestro into a Black Lantern. He then reanimates the Sinestro Corps as Black Lanterns and they attack the Apex League.[76]

Sinestro first appears in the Year Two series of the prequel comic to Injustice: Gods Among Us. He intercepts Green Lantern Kyle Rayner before he can reach Earth. Revealing his knowledge of all the changes that have taken place the previous year, Sinestro has his Corps kill Rayner before he approaches the Watchtower. He is nearly beaten by a more vicious Superman before he reveals that he has actually come to join Superman's cause, seeing that the Kryptonian has undergone a change in personality and tactics to "save" the world. Sinestro is briefly kept as a prisoner at the Hall of Justice as he explains his own downfall and expulsion from the Green Lantern Corps: in his eyes, he had been a well-meaning Lantern who only wanted to save and better his world, just for the Green Lanterns to deem him a tyrant and stop him. However, he was clearly a dictator who drove his wife Arin to suicide and lost his daughter as a result of his actions. Sinestro felt particularly betrayed when his former comrades—including his protege Hal Jordan—stopped him and removed his ring, expelling him from the Corps. Sensing that he and Sinestro have similar backgrounds (as Superman lost his wife and unborn child to crime), Superman allows him to join the Regime, though Hal Jordan is not happy about this when he returns to Earth after being subdued by the Green Lanterns. He is forced to work with Sinestro during the annual, where he and Sinestro face their tense relationship as they look for a device that could destroy a whole planet. They come closer after Sinestro destroys a device that could give Superman greater power, ensuring no one could have it. Sinestro continues to play a key role in creating forced order across the world, even staging an event where Despero looked like he was attacking and Sinestro was forced to kill him in self-defense. He subsequently kills John Stewart and manipulates Hal into believing that Guy Gardner was the one who killed him, thus making Hal mistakenly kill Guy. After Hal Jordan was stripped of his Power Ring by Ganthet for choosing Superman's Regime over the Green Lantern Corps, Sinestro gives Hal a Qwardian Power Ring, allowing Hal to become Yellow Lantern and save his love Carol Ferris.

In Green Lantern: Earth One, a pseudo-Lantern resembling Sinestro is among those who respond to Hal Jordan's distress call and participates in the recovery of the Central Power Battery from the Manhunters.

Sinestro appears in Duck Dodgers, voiced by John de Lancie. In the episode "The Green Loontern", he attempts to kidnap all the Green Lanterns but is stopped by Duck Dodgers himself. Dodgers pointed out Sinestro's devilish appearance to him.

In Static Shock, Sinestro appears in the episode "Fallen Hero" disguised as John Stewart (voiced by Phil LaMarr) for a good portion of the episode. After he steals Stewart's battery following a fake distress signal he created, Sinestro attacks Dakota disguised as his nemesis. With help from Static, Stewart managed to defeat Sinestro.

Sinestro appears during the fifth season of The Batman, voiced by Miguel Ferrer. Just like the comics, Sinestro served as Hal Jordan's teacher in the Green Lantern Corps until he went power hungry and was stopped by the Green Lantern Corps. This version of Sinestro has a rather bulbous upper cranium and a longer mustache than usual, resembling a horseshoe or Fu Manchu than his usual pencil style. In the episode "Ring Toss", Sinestro escaped from his prison and goes to Earth where he attacked Green Lantern (before having a chance to recharge the power ring) at the airport as Hal Jordan sends the Power Ring to Batman. However, Penguin ended up with the Power Ring and used it to commit a series of petty thefts. He fought Batman, Robin, and Jordan. Sinestro, however, attacked Penguin, calling Penguin stupid and unworthy to possess the ring. When Penguin ended up reluctantly giving the ring to Batman, Batman placed the ring on his own finger to fight Sinestro. When the Power Ring started to weaken and sputter as Penguin had expended much energy due to foolishness, Jordan recharged the power ring and helped Batman fight Sinestro where Sinestro was disarmed of his ring by Batman (who ironically opened his hand with Sinestro's power ring in it) who then knocked out Sinestro. Green Lantern then took Sinestro back to his cell.

Sinestro (as a Green Lantern) appears in Batman: The Brave and the Bold, voiced by Xander Berkeley. In "The Eyes of Despero!", he helped Batman, Guy Gardner and G'nort defeat Despero. He along with G'nort and Gardner were freed from an Oan holding cell by Batman transported by Hal Jordan's ring to Oa to help the remaining members after Despero seemingly destroys all the active members. He and the others empower Batman's suit for the job. When Batman was fighting Despero, the Dark Knight learned that Sinestro was in jail for destroying the Okaran warships, taking every living being on those ships with them. Sinestro then created a puppet government loyal only to him. He attempted to blow up Mogo, only to be stopped by Gardner. Gardner imprisoned Sinestro in his ring at the end. A heroic version of Sinestro appears in "Deep Cover For Batman", with a yellow costume that resembles Hal Jordan's costume. His yellow outfit and yellow power ring are homage to the Sinestro Corps.

Sinestro appears in Green Lantern: The Animated Series, voiced by Ron Perlman. In the episode "Prisoner of Sinestro", Hal Jordan and Kilowog receive a distress call from Sinestro, whom Hal reveres as a legendary Green Lantern, to rescue him and his captive—a body-jumping alien he has illegally captured on a mission for the Guardians. Onboard Hal's space cruiser, Sinestro is briefly possessed by the alien and attacks the crew. Later, they determine the alien consciousness is hopping bodies and cannot be pinned down. Realizing that it cannot use the power rings of those it possesses, Sinestro depressurizes the ship to flush it into the open, as power rings protect their wearers in deoxygenated environments. It returns to its host body and enters a state of shock, while Sinestro privately gloats that he left the sciencell depressurized on purpose to kill the creature, in violation of the Green Lantern code. He reports its death to Hal and his crew as a tragic accident, but his coldness regarding the death of his captive leaves Hal suspecting that his former mentor may have crossed a line. In an interview with producer Giancarlo Volpe, Volpe revealed that, had the show not been canceled, Sinestro would've return in the Season Two premiere where he framed Hal Jordan for his crimes.

Sinestro appears in the Justice League Action episode "The Ringer," voiced by Darin de Paul.[77] He is shown fighting Hal Jordan with power from his overcharged ring. While Superman and Wonder Woman aid Jordan, The Atom goes in Sinestro's ring and fights his way past the fear to find the source. Atom finds the ring's battery source inside being guarded by Despotellis. Sinestro is alerted about Atom by Despotellis as he orders him to deal with Atom. While Sinestro continues his fight with Jordan, Superman, and Wonder Woman, Atom deals with Despotellis. After Atom defeats Despotellis, Sinestro's power ring runs low as Hal defeats him.

Victor Garber voices Sinestro as the main antagonist in the Warner Premiere animated feature Green Lantern: First Flight. In the film, Sinestro is a respected member of the Green Lantern Corps who believes the Guardians and the Corps aren't proactive enough to maintain order of the universe. Seeking to overthrow Oa in order to instill his brand of order through fear, he collaborates with Corps member Boodikka and dictator Kanjar Ro in search of the Yellow Element to create a weapon that could destroy the Corps. He later frames the newly recruited Hal Jordan for Ro's death before seeking the weapon made from the element by the Weaponers - the yellow ring and power battery. After Sinestro defeats the Guardians and the Green Lantern Corps, Jordan absorbs the Guardians' Green Element power source and challenges the despotic Korugarian. The yellow power battery is destroyed by Jordan and Sinestro's ring, along with his hand, is crushed by Kilowog. Sinestro's was most likely put into a prison cell for his crimes. When Sinestro takes possession of the yellow ring, his costume is changed from a Green Lantern uniform to his Sinestro Corps uniform. However, the ring itself is just a yellow copy of a Green Lantern ring, although much more powerful thanks to the yellow weakness of the green rings.

Jason Isaacs voices Sinestro in the animated anthology film Green Lantern: Emerald Knights.[78] In the film, he is still a member of the Green Lantern Corps. During the fight of Atrocitus with his friend Abin Sur, Sinestro remarks: "If I had a power ring for every time I'd heard that, I'd have my own Corps," alluding to the Sinestro Corps. The Sinestro Corps is shown in Atrocitus's "vision" to Sur, upon being re-imprisoned.

Mark Strong portrays Sinestro in the live-action film Green Lantern. Presented as a respected member of the Green Lantern Corps, he is dedicated to his duty with benevolent intentions to defeat Parallax throughout the film, and suggests that the Guardians of the Universe create a yellow ring of fear forged from a portion of Parallax's power in order to defeat the fear entity. Hal Jordan manages to convince the Guardians that giving into fear to stop fear will not solve anything and the yellow ring the Guardians created is sealed away. At the end of the film, after Parallax is defeated by Jordan, Sinestro is shown breaking the seal to the yellow fear ring and swapping his own Green Lantern ring for it. Sinestro's Green Lantern uniform becomes recolored yellow and he's shown to now revel in his new power over fear, marking his eventual turn from the Green Lantern Corps and the Guardians of the Universe.[79]

Sinestro makes a silent cameo appearance in the theatrical animated film Teen Titans Go! To the Movies, based on the Teen Titans Go! animated series. In the film, after the Teen Titans travel to the past and prevent the origins of the core members of the Justice League came to pass so Jade Wilson could make a film about them, when they return to the present, given the absence of superheroes, all the villains cause havoc in the world. Sinestro appears chasing three civilians with a lantern Pac-Man, even though Green Lantern's origin wasn't prevented. Upon witnessing this, the Titans return to the past and undo their blunder.

Sinestro appears in DC Universe Online, voiced by Robert Kraft. His ring and the rings of the Sinestro Corps have been experiencing malfunctions and they blame the Green Lantern Corps. This spurs a battle between the two groups which eventually led to a showdown between Sinestro, John Stewart and their respective Corps members. Upon being defeated, Sinestro escaped with John and the other Green Lantern Corps members after him since Sinestro won't get far with whatever power is left in his power ring.

Sinestro appears as a playable character in Injustice: Gods Among Us, with Troy Baker reprising his role. At the beginning of the game, he is seen fighting the Justice League with other allies. In an alternate reality, Sinestro allies with Superman's Regime on Earth. Unlike the other villains who are part of Superman's Regime, Sinestro was not coerced by any means by Superman to join the Regime; he appears somewhat self-subsiding and appears to have higher ranking over most other Regime members, given permanent control of some ground forces. He also states that he still rules over Korugar with his own regime. In the story, Sinestro gives the Hal Jordan of that Earth a Sinestro Corps ring after he sides with Superman's new violent methods, turning his former nemesis into a Yellow Lantern. However, he does not serve any major role in the story otherwise. At the game's conclusion, Sinestro is defeated by the "prime" Superman and disarmed of his ring. He and Yellow Lantern are taken to Oa by "prime" Hal Jordan to stand trial for their actions. In Sinestro's single player ending after defeating Superman, he realizes that Fear is not powerful enough to bring order to the universe. Throwing the full might of the Sinestro Corps against the Life Entity that holds the White Lantern Power Battery, Sinestro is victorious. Wielding the power of the battery as a White Lantern, he plans to destroy all who stand in his way, beginning with the Green Lantern Corps.

Sinestro is mentioned in Injustice 2 by Atrocitus, who recaps Hal Jordan's story in Injustice: Gods Among Us. In Hal's arcade mode ending it is revealed that Sinestro managed to escape from the Green Lantern Corps' science cells and return to the Sinestro Corps before Jordan's return. This leads Hal to go undercover as a Yellow Lantern while trying to keep the yellow ring's fear spectrum from controlling him.

Sinestro appears in Lego Batman 2: DC Super Heroes, voiced by Troy Baker. He is a boss fight and unlockable character, found in the Central Metro Station. In the Xbox 360 version, an achievement named "Green Lantern's Light" is unlocked after player defeats him as Green Lantern.

Sinestro appears as a playable character in Lego Batman 3: Beyond Gotham, voiced by Marc Worden. He plays a bigger role in the game than in his previous appearance, first appearing in the opening of the story fighting alongside Larfleeze and Atrocitus against Saint Walker, Star Sapphire and Indigo-1 until they are captured by Brainiac to fuel the shrink ray. After the device is disabled, he is sent back to Qward. Unlike Larfleeze and Atrocitus being distracted by the villain-disguised heroes while Hal Jordan takes their power batteries, Sinestro is the only one who is not fooled by their act and attacks them, though they are successful to take his power battery as well. In the game's climax, he, alongside Atrocitus and Larfleeze, confronts the heroes in the Fortress of Solitude to take their batteries back, only to have their energies focused in a crystal created by Superman to return Earth to its rightful size, and Sinestro, calling this a 'waste of trip', is teleported back to Qward again. In a mid-credit scene, he is seen vowing to destroy the Earthlings as he bumps into Wonder Woman's Invisible Jet which takes off on its own.